Abstract:
This study was conducted in the medical laboratories in Kosti city. The
laboratories comprised the governmental, non governmental and private
sector labs, to evaluate the result of malaria diagnosis by microscopy. 524
samples were taken by different laboratories. From each individual, a
duplicate sample was taken for follow up by the investigator. From the blood
sample, thick and thin smears were prepared, stained by Giemsa and
examined microscopically to compare the results of each laboratory. The
smears were examined by the investigator, in addition some of the slides
examined by the laboratories under servey were sent to the reference
laboratory of malaria administration in kosti for further confirmation of the
results. The results were as follows:
The rate of the false positive results in all laboratories reached 63%.
The highest false results (79%) were reported by the governmental
laboratories, while the non governmental laboratories and private
laboratories reported 55 % and 48 % false results respectively.
The difference was found to be statistically significant.
Although the collection of the samples was done properly the
percentage of the false positives reached 67% and when collection of
the samples was done in properly, the percentage reached 63%.
The study showed that when blood smears were done properly, the
false positives rate reached 20%, and when the blood smears were
done improperly the rate reached 65%.
When the smears were properly stained, the false positives rate was
30% and when the smears were improperly stained, the rate was 69%.
When evaluating the effect of the general condition of the laboratory
(building, electricity and water supply, space and cleanness) on the
performance of the result the false positives reached 63% in both good
and bad condition laboratories.
Despite the use of good and efficient microscopes the rate of false
positives results reached 67% and 50% when inefficient microscopes
were used.
The study showed that, when a good quality immersion oil, was used
the false positives results was 46% and reached 83% when the quality
of immersion oil is bad.
The study showed that the false positive result reached 77% among
personnel who did not receive training in malaria and 39% in those
who received training in malaria.
The result revealed that the false positive rate was 29% among those
samples examined by university graduates, while it reached 69%
among those holding diplomas. The rate reached 74% among the
samples examined by mixed graduates.
